For example, in a manufacturing process of a semiconductor device, photolithography processing is performed in which a resist coating treatment of applying a resist solution onto, for example, a semiconductor wafer (hereinafter, referred to as a “wafer”) to form a resist film, exposure processing of exposing the resist film to a predetermined pattern, a developing treatment of developing the exposed resist film and so on are performed in sequence to form a predetermined resist pattern on the wafer. Then, using the resist pattern as a mask, an etching treatment is performed on a film to be treated on the wafer and a removal treatment of the resist film is then performed, to form a predetermined pattern in the film to be treated.
Incidentally, miniaturization of the above-described pattern of the film to be treated is required in recent years in order for higher integration of the semiconductor device. Therefore, miniaturization of the resist pattern is in progress and, for example, the wavelength of light for the exposure processing in the photolithography processing is being shortened. However, there are technical and cost limits in shortening the wavelength of an exposure light source, and it is now difficult to form a fine resist pattern at a level of, for example, several nanometers only by the method of increasingly shortening the wavelength of light.
Hence, there is a proposed wafer treatment method using a block copolymer composed of two kinds of, hydrophilic and hydrophobic block, chains (polymers) (Patent Document 1). In this method, first, a neutral layer having an intermediate affinity to the two kinds of polymers is formed on the wafer, and a guide pattern is formed, for example, of a resist on the neutral layer. Thereafter, the block copolymer is applied onto the neutral layer, and the block copolymer is phase-separated into the two kinds of, hydrophilic and hydrophobic, polymers to form a lamellar structure. Thereafter, one of the polymers is selectively removed, for example, by etching or the like to form a fine pattern composed of the other polymer on the wafer. Then, the pattern of the polymer is used as a mask, an etching treatment is performed on the film to be treated to form a predetermined pattern in the film to be treated.
[Patent Document 1] Japanese Patent Application Laid-open No. 2008-36491